Mushroom Supplements for People With Cancer: What to Tell Your Care Team
What research and cancer agencies say about turkey tail, reishi and maitake products, why a supplement differs from a regulated medicine, and what to tell your oncology team.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
If you or someone you love has cancer, mushroom products can look like a gentle way to help. This page explains what the sources we read actually say, and why the most important step is telling your oncology team about every product you use or are thinking of using, before you start. It is information only. It is not advice to start, stop or change anything, including any prescribed treatment. Your oncologist and pharmacist decide what is right for you.
- The US National Cancer Institute (NCI) says the FDA has not approved medicinal mushrooms as a treatment for cancer or any other medical condition. [1]
- The National Center for Complementary and Integrative Health (NCCIH) says no complementary health approach has been shown to prevent or cure cancer. [2]
- Some mushroom products can affect bleeding, blood sugar, the immune system or the liver, and some have been reported to interact with medicines. These points are listed below with their sources.
- Do not use a mushroom product in place of, or to delay, cancer treatment. NCCIH warns against replacing or delaying medical treatment with unproven products. [2]
A medicine in Japan is not the same as a supplement here
Turkey tail (Trametes versicolor (L.) Lloyd, also written Coriolus versicolor) is listed as an accepted name in GBIF, and NCI uses the same names. [3][4] NCI describes polysaccharide K (PSK) as the best known compound from turkey tail and says that in Japan PSK is an approved mushroom product used to treat cancer. [4] NCI also states that the FDA has not approved turkey tail or PSK as a treatment for cancer in the United States. [4]Why this matters: trial results for a standardized, regulated extract do not transfer to a capsule, powder or tea bought as a supplement. NCI notes that supplement ingredients may vary considerably from lot to lot and that there is no guarantee that ingredients claimed on labels are present in the stated amounts. [1] See PSK, PSP and lentinan and how mushroom supplements are regulated.
What research found
Traditional use is described separately: NCI says medicinal mushrooms have been used for hundreds of years, mostly in Asia. [4] That is tradition, not proof for any person with cancer.| Mushroom and form | What the source found | Who it applies to | Our label |
|---|---|---|---|
| Turkey tail, PSK extract, added to chemotherapy or radiotherapy | A Cochrane review of seven randomized trials (1569 participants, mostly in Japan) found low-certainty evidence of a small survival benefit at five years; effects on side effects of treatment were uncertain (very low certainty) [5] | Adults with colorectal cancer, extract used after surgery with older chemotherapy regimens | promising but limited |
| Turkey tail, whole preparation, 3, 6 or 9 grams a day for six weeks | A phase I safety trial of 11 women (nine finished) after breast cancer radiotherapy reported nine adverse events (seven mild, one moderate, one severe) and trends in some immune measures; it was not a test of cancer outcomes [6] | Women with breast cancer, small dose-escalation trial | insufficient evidence |
| Reishi (Ganoderma lucidum (Curtis) P.Karst.) | NCI states there are no studies of G. lucidum with measured cancer outcomes [1] | Not applicable | insufficient evidence |
| Maitake (Grifola frondosa (Dicks.) Gray) | A cancer-center reference says clinical data are limited, with small trials of immune effects [7] | Small studies, various products | insufficient evidence |
The Cochrane authors also noted that the chemotherapy regimens in these trials do not reflect current preferred practice, and that it was unclear whether any adverse events were due to chemotherapy or to the extract. [5] Laboratory and animal findings are not the same as results in people; see human studies versus animal and lab research and mushrooms and cancer claims.
What to tell your care team
Bring the actual product or a photo of the label, and be ready to say:- The mushroom and its scientific name, and whether it is fruiting body, mycelium or mycelium on grain; see fruiting body versus mycelium.
- The form (capsule, powder, tea, extract, coffee) and how often you use it.
- Every other supplement, herb, vitamin and over-the-counter medicine, including antioxidant products. NCCIH notes that antioxidant supplements might interfere with the effectiveness of chemotherapy or other cancer therapies. [2]
- Any planned surgery or scan. See mushroom supplements before surgery.
- Any transplant, autoimmune condition or liver or kidney problem; see mushrooms, autoimmune conditions and transplants.
Useful questions: Could this affect my treatment or my blood tests? Is there a regulated alternative, or a supportive-care approach with better evidence? A pharmacist can check a specific product against your medicines; see how interactions work and mushroom supplement and medicine interactions. For products promoted as alternatives to treatment, see what studies found on choosing alternative medicine instead of cancer care.
Frequently asked questions
Can mushroom supplements treat cancer?
No supplement is shown to cure cancer, and the FDA has not approved medicinal mushrooms to treat cancer or any other condition. [2][1]
Is turkey tail the same as the cancer medicine used in Japan?
Not necessarily. PSK is a specific extract approved in Japan, and NCI says the FDA has not approved turkey tail or PSK for cancer treatment in the United States. [4]
Should I take reishi or turkey tail during chemotherapy?
That is a decision for your oncologist and pharmacist. Sources note possible effects on bleeding, immune medicines and chemotherapy, and for reishi a theoretical interaction. [8]
Can a mushroom supplement change my lab tests?
One cancer-center reference reports higher CA72-4 tumor marker levels after reishi spore supplements, and reishi extracts may prolong clotting tests. [8] Tell your team about every product.
Does Cochrane say turkey tail helps colorectal cancer?
Cochrane found low-certainty evidence of a small survival effect at five years for a PSK extract and was uncertain about effects on treatment side effects. [5]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Cautions that sources document
- Reishi and bleeding. A cancer-center reference says reishi can increase the risk of bleeding and advises talking to a healthcare provider if you take blood thinners such as warfarin. [8]
- Reishi and immune medicines. The same reference advises talking to a healthcare provider if you take immunosuppressants. [8]
- Reishi and chemotherapy (theoretical). It says reishi can raise antioxidant capacity and, in theory, may interact with chemotherapy agents that rely on free radicals. [8] This is a theoretical concern, not a documented harm.
- Reishi and the liver. It lists a case report of liver toxicity with powdered reishi, leading to death in one instance. [8] See reishi side effects and liver reports.
- Reishi and tumor marker tests. In patients treated for gastrointestinal cancer, levels of the tumor marker CA72-4 were higher after taking reishi spore supplements. [8] Tell the team so a lab result is not misread.
- Maitake. The same reference says maitake can increase the risk of bleeding and can lower blood sugar, and it describes a case report of a warfarin interaction. [7]
- Herbal supplements in general. NCCIH says some may interact in harmful ways with drugs, including those used in cancer treatment. [2]
Turkey tail safety is covered on turkey tail safety and side effects; NCI reports that few side effects have been described in studies of PSK in Japan. [4] That statement is about the studied extract, not every product.
References
- National Cancer Institute. Medicinal Mushrooms (PDQ), Health Professional Version. Latest update 11/06/2024. Read 2026-10-23.
- National Center for Complementary and Integrative Health. Cancer and Complementary Health Approaches: What You Need To Know. Last updated October 2021. Read 2026-10-23.
- GBIF Secretariat. GBIF Backbone Taxonomy species match for Trametes versicolor, Ganoderma lucidum, Cordyceps militaris, Ophiocordyceps sinensis, Grifola frondosa and Lentinula edodes. Read 2026-10-23.
- National Cancer Institute. Medicinal Mushrooms (PDQ), Patient Version. Read 2026-10-23.
- Pilkington K, Wieland LS, Teng L, et al. Coriolus (Trametes) versicolor mushroom to reduce adverse effects from chemotherapy or radiotherapy in people with colorectal cancer. Cochrane Database Syst Rev. 2022;11:CD012053. PubMed 36445793. Read 2026-10-23.
- Torkelson CJ, Sweet E, Martzen MR, et al. Phase 1 clinical trial of Trametes versicolor in women with breast cancer. ISRN Oncol. 2012. PubMed 22701186. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center. Maitake: About Herbs, Botanicals and Other Products. Last updated 9 July 2026. Read 2026-10-23.
- Memorial Sloan Kettering Cancer Center. Reishi Mushroom: About Herbs, Botanicals and Other Products. Last updated 5 May 2026. Read 2026-10-23.